I changed out the aluminum cooling tubes today because they were getting worn through.
I drained the coolant by simply disconnecting the silicone hoses. I then pulled a vacuum on the system down to 25mm and refilled the system with some water wetter solution.
The car at idle in my 90 plus degree shop is getting up to 237 degrees (!!!!) and the coolant overflow tube spewed out.
I'm wondering if
1) I didn't get all of the original coolant out
2) I've got huge air pockets
I could use some basic instruction on how you drain the coolant and refill.